From: Eric Dumazet <edumazet@google.com>
Date: Tue, 28 May 2024 12:52:52 +0000 (+0000)
Subject: tcp: fix races in tcp_abort()
X-Git-Tag: microblaze-v6.13~667^2~295^2~1
X-Git-Url: http://git.monstr.eu/?a=commitdiff_plain;h=5ce4645c23cf5f048eb8e9ce49e514bababdee85;p=linux-2.6-microblaze.git

tcp: fix races in tcp_abort()

tcp_abort() has the same issue than the one fixed in the prior patch
in tcp_write_err().

In order to get consistent results from tcp_poll(), we must call
sk_error_report() after tcp_done().

We can use tcp_done_with_error() to centralize this logic.

Fixes: c1e64e298b8c ("net: diag: Support destroying TCP sockets.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240528125253.1966136-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 2a8f8d8676ff..5fa68e7f6ddb 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -4576,14 +4576,10 @@ int tcp_abort(struct sock *sk, int err)
 	bh_lock_sock(sk);
 
 	if (!sock_flag(sk, SOCK_DEAD)) {
-		WRITE_ONCE(sk->sk_err, err);
-		/* This barrier is coupled with smp_rmb() in tcp_poll() */
-		smp_wmb();
-		sk_error_report(sk);
 		if (tcp_need_reset(sk->sk_state))
 			tcp_send_active_reset(sk, GFP_ATOMIC,
 					      SK_RST_REASON_NOT_SPECIFIED);
-		tcp_done(sk);
+		tcp_done_with_error(sk, err);
 	}
 
 	bh_unlock_sock(sk);